C CDCY      SOURCE    CHAT      05/01/12    21:51:18     5004           
C CDCY     SOURCE    INSL       24/10/96    
      SUBROUTINE CDCY(EPEQ,SEQ,IPL,PENT,EX,TU,EMAX,EPO,ICAL)
C
      IMPLICIT INTEGER(I-N)
      IMPLICIT REAL*8(A-H,O-Z)
C
C                  *******************************
C                  *** COURBE DE COMPRESSION   ***
C                  ***     UNIAXIALE           ***
C                  *******************************
C-------------------------------------------------------------------
      IF(EPEQ .GE.EMAX) THEN
        SEQ =0.D0
        IPL = 4
        PENT=0.D0
        GOTO 10
      ENDIF
C-------------------------------------------------------------------
      IF(ICAL.EQ.1) THEN
C            ******************************
C            **    PRE-PIC   LINEAIRE    **
C            ******************************
        IF(EPEQ.LT.EPO) THEN
          SEQ =EX*EPEQ
          PENT=EX
          IPL = 0
        ELSE
          SEQ =TU*(EMAX-EPEQ)/(EMAX-EPO)
          PENT=-TU/(EMAX-EPO)
          IPL =2
        ENDIF
        GOTO 10
      ENDIF
C-------------------------------------------------------------------
C            ******************************
C            ** COURBE DE COMPRESSION   ***
C            **      INSA-LBS1          ***
C            ******************************
      IF(EPEQ.LT.EPO) THEN
        B3=EX/TU-2.D0/EPO
        C3=1.D0/EPO/EPO
        DIN3=1.D0+B3*EPEQ+C3*EPEQ*EPEQ
        SEQ=EX*EPEQ/DIN3
        PENT=EX*(1.D0-C3*EPEQ*EPEQ)/DIN3/DIN3
        IPL = 0
      ELSE
        SEQ=TU*(EMAX-EPEQ)/(EMAX-EPO)
        PENT=-TU/(EMAX-EPO)
        IPL=2
      ENDIF
C-------------------------------------------------------------------
   10 CONTINUE
      RETURN
      END